2 alpha-(2',2'-disubstituted-2'-hydroxy-ethoxy)tropane (2 alpha-DHET cholinolytic, is a racemic tertiary amine with two chiral carbonic atoms. It has four optical isomers whose absolute configurations are 1R-2 alpha-2'S, 1R-2 alpha-2'R 1S-2 alpha'R and 1S-2 alpha-2'S. These compounds showed both antimuscarinic and antinicotinic activity, blocking both muscarinic and nicotinic receptors. Central muscarinic receptors, rather than nicotinic receptors, have a stereoselective specificity to these compounds. The 2'R configurations are more suitable to the stereostructure of the binding site of muscarinic receptors than the 2'S configuration.